Retaining device for railroad car doors



Nov. 30, 1965 T. 2. HERR 3,220,063

RETAINING DEVICE FOR RAILROAD CAR DOORS Filed May 22, 1963 2Sheets-Sheet 1 FIG. I

22 2| L# n II I I I J I I I I I F J IE] X 29 28 30 I6 47 I9 \II [IF 2 oI I 10A 1L: I \34 I3 24 3 I 25 INVENTOR. THEODORE Z. HERR AT T0 R NEYSNov. 30, 1965 T. Z. HERR RETAINING DEVICE FOR RAILROAD CAR DOORS FiledMay 22, 1963 2 Sheets-Sheet 2 #34- 44 4s A y INVENTOR. 2;; r: ,I

L THEODORE Z.HERR -I P. h flu BY I I I l V j a 3 [0 45 43 MAXIMUMTRAVELi g 3 BEFORE LATCHING ATTORNEYS United States Patent corporation of OhioFiled May 22, 1963, Ser. No. 282,401 6 Claims. (CI. 20-23) Thisinvention relates to a sliding railroad car door and more specificallyto a mechanism for restraining the sliding movement of such car doors.

In its broadest aspect, this invention relates to a lever system forcontrolling the operation of a latching device.

In its most specific aspect, the invention contemplates a latchingdevice secured to a railroad car door with the latching devicefunctioning to secure the door in a plurality of adjusted positionsthereby to restrain the door from free rolling movement.

The plug door is a commonly used type of door in the railroad carindustry and is one which is flush with the external siding of therailroad car when in the closed position. To expose the door opening, itis necessary to displace the door laterally away from the side of thecar and along slide tracks longitudinally the length of the car. Thesedoors are attached to the car through rollers mounted on a track andrepresent a potentially freerolling body, but ordinarily move with thecar until the car has encountered a decelerating or accelerating force.Upon application of an external decelerating or accelerating force onthe car and inasmuch as the doors are ordinarily mounted for movementrelative to the car on rollers having a minimum of friction, the door,due to its inertia, continues at its initial velocity until restrainedby an external force.

This external force heretofore has taken the form of a stop secured tothe side of the car which abruptly halts the rolling movement of thedoor at the completion of its travel. Since these railroad car doors areof a considerable weight and are brought to a halt within a very shortdistance, the forces on the door frequently are in the order of 70,000lbs. Obviously, with forces of this magnitude acting on the door,considerable damage frequently results from the impact.

In order to lessen the effects of the restraining impact, it would beconceivable to extend the distance over which the restraining force isapplied and thereby reduce the adverse elfects on the door. However,this is impractical because of the expense and space limitations.

Accordingly, it is an object of this invention to provide a device for arailroad car door to minimize the restraining forces on the door.

Another object of this invention is to provide a means for restrainingthe free rolling movement of a railroad car door.

It is a further object of this invention to provide a latching devicefor a railroad car door wherein the door may be secured in a pluralityof adjusted positions along the longitudinal length of the supportingtrack.

It is a still further object of this invention to provide a latch devicefor restraining movement of a railroad car door which latch device isinexpensive and of minimum dimensions and easily attached to existingdoors.

It is another object of this invention to provide a lever system forcontrolling the operation of a latching device on a railroad car door.

It is a more specific object of this invention to provide a latchingdevice for restraining a railroad car door wherein a plurality of slotsare provided in the car door track and a spring biased latch deviceincluding a manually operable handle are secured to the car door withthe latch "ice device being receivable in any selected one of the slotsin the track thereby securing the car door in an adjusted position alongthe longitudinal length of the track.

It is a still more specific object of this invention to provide arailroad car door restraining mechanism including a plurality of slotsin the car door supporting track, a spring biased latched mechanismsecured to the car door with the latch mechanism including a portionreceivable in the slots in the track, and a manually operable leverpivotally mounted on the car door and operable to pivot the latchingmechanism against the bias of its biasing means thereby to remove therestraint on the car door.

To the accomplishment of the foregoing and related ends, said inventionthen consists of the means hereinafter fully described and particularlypointed out in the claims, the following description setting forth indetail one approved means of carrying out the invention, such disclosedmeans, however, constituting but one of the various ways in which theprinciples of the invention may he used.

In the drawings:

FIG. 1 is a front elevational view showing the invention as it isincorporated on a railroad car door;

FIG. 2 is a fragmentary side elevational view taken along line 2-2 ofFIG. 1 showing the latching mechanism;

FIG. 3 is a front elevational view of the latching mechanism illustratedin FIG. 2.

Referring now to the drawings which illustrate one preferred embodimentof the invention, the numeral 10 designates one side wall of aconventional railroad car. A door opening 11 is formed in the side walland is adapted to be closed by a laterally movable door 12. In theclosed position, the door 12 is seated in the door opening and issubstantially flush with the external surface of the side wall 10.

To move the door laterally out of the door opening 11 for longitudinalmovement along the side wall 10 on track 13, there are provided spacedapart parallel vertical pipes 14, 15. Each of the pipes 14, 15 isrotatably secured to the door 12 by means of brackets 16, 17, 18, 19.Secured to the upper end of the pipes 14, 15 are cranks 20, 21,respectively. The cranks 20, 21 extend upwardly behind a retainer 22 andare provided with rollers which guide the door in its longitudinalmovement and retain the upper portion of the door in the proper positionrelative to the car. Secured to the lower end of each of the pipes 14,15 are cranks 24, 25 respectively. The cranks 24, 25 are journalled inroller hangers 26, 27 mounted upon the track 13 thereby to facilitatesliding movement of the door 12. It is believed apparent that uponrotation of the pipes 14, 15, the upper cranks 20, 21 and the lowercranks 24, 25 are caused to rotate. As is apparent from an inspection ofFIG. 1, all of the cranks 20, 21, 24, 25 are normal to the plane of thedoor when the door is in the closed position. Thus, upon rotation of thepipes 14, 15, the cranks are pivoted to a position approximating aparallel relationship with the door thereby causing the door to bedisplaced laterally outward from the plane of the cars siding. Afterthis has been accomplished, the door may be displaced longitudinallyalong the track 13 thereby exposing the door opening.

To accomplish the rotation of the pipes 14, 15, there is provided a pairof operating levers 28, 29. The free end of the levers 28, 29 arerestrained in a latch mechanism 30 with the opposite ends of each of thelevers being pivotally secured to clevises 31, 32 respectively. Theclevises 31, 32 are attached to pipes 14, 15 so that upon rotation ofthe levers 28, 29 a corresponding rotation is imparted to the pipes.

Inasmuch as rollers are mounted on the upper ends of the cranks 20, 21and the cranks 24, 25 are received on roller hangers 26, 27, it isbelieved apparent that the door, when displaced laterally from the dooropening, constitutes a body capable of free rolling movement along track13. As such, the door, due to its weight and iner tia, will react to anyexternal force applied to the car independently of the reaction of thecar itself. Thus, assuming the car to be moving at a constant velocity,the door will be at rest relative to the car and will be moving at thesame velocity as the car. However, should the car receive anaccelerating or decelerating force, the door wouldtend to maintain aconstant velocity and, due to its free rolling characteristics, wouldroll along the track 13. Assuming the car is brought to an abrupt halt,the door would roll along the track substantially at its originalvelocity until it is halted by the fixed stop device commonly providedon the side of the railroad car.

The effect of the door reacting against a fixed stop on the car is todeliver a blow of substantial magntitude to the door. Assuming a cardoor of approximately 1200 lbs. and moving at a velocity of from to mph,the effect of the usual rigid stop device is to impart a blow ofapproximately 70,000 lbs. to the car door. Obviously, impacts of thismagnitude are the occasion of substantial damage to the door and devicesadequate to absorb this energy are difficult to design within the spaceand cost limitations.

A further problem represented by the existing doorandstop arrangement isthe tendency of the door to be lifted from the track during impactcausing permanent detrailment of the car door. Such a situation occursdue to a couple resulting from the impact, which couple tendsto causethe lower rear corner of the door to be raised from the track. Once thedoor is lifted from the track, the roller hanger is dropped and the dooris derailed.

As a solution to these problems, there is illustrated in FIGS. 2 and 3 alatching mechanism which serves to retain thecar door in any adjustedposition along the track thereby restraining its free-rollingcharacteristics. The latching mechanism comprises a latch designatedgenerally by the reference numeral 33. This latch consists of anessentially bellcrank lever having a depending leg 34 and bifurcated armportions 35a and 35b. The latch 33 is pivotally received'on a pivotmember 36 which in turn is journalled in supporting brackets 37, 38secured to the car door 12. A torsion spring 39 is mounted on the pivotpin 36 with one portion 40 of the spring 39 abutting the depending leg34 and the other portion 41 of the spring 39 being in abutment with thebracket plate 42.

The latch 33 under the bias of the spring 39 tends to pivot in aclockwise direction around the pivot 36 as viewed in FIG. 2. However,the latch is restrained from a free pivoting movement due to theabutment of the oifset end 43 of the depending leg 34 with the track 13and the abutment of arms 35 with plate 42.

Provided in the track 13 is a plurality of openings or slots 44separated by land portions 45 with the alternate land and slotarrangement being provided along the entire longitudinal length of thetrack 13. It is to be noted that the slots 44 are provided in but oneleg of the track 13 with the slots facing inwardly toward the railroadcar; the other leg of the track 13 covers the slots so that hand contactwith the slots is prevented. Projecting from the lower portion 43 of thedepending leg 34 is a lug 46 which is receivable in the slots 44. Withthe lug 46 received in any of the slots 44, the car door is restrainedfrom movement relative to the track 13 thereby preventing the freerolling and resulting impact described above.

The bias of the spring 39 serves to maintain the offset portion 43 ofthe depending leg 34 in engagement with the track 13 and thus retain thelug 46 in one of the slots 44. In order to remove the lug 46 from theslot 44, there is provided an actuating handle 47 which is independentlypivotally secured at 48 to the upper end 49 of the bracket plate 42. Theseparate mounting of the handle 47 permits a limited amount ofindependent pivoting movement for the handle relative to the door andthe latch. The handle 47 is disposed vertically along the face of thedoor 12 and has offset arms 50a, 5% adapted to abut the arms 35a, 35brespectively. However, in the normal upright position of the lever 47,both of the arms 50a, 5012 are removed from the abutting relationship.Should the handle 47 be pivoted to the position shown in dotted lines inFIG. 3, the arm 50b would abut the arm 35b of the latch 33 causing thelatch to pivot about the pin 36 against the spring bias of the spring39. This pivoting movement of the latch 33 would retract the lug 46 fromthe slot 44 in the track 13 thereby releasing the doorfor slidingmovement longitudinally of the track. Similarly, should the handle bepivotedcounterclockwise, as viewed in FIG. 3, the arm 50:: would abutarm 35a and thereby retract the lug 46 from its associated slot.

The latching mechanism described here remains operative so long as thedoor is in the fully opened. position and will automatically latch thedoor in a position along the track upon release of the lever 47. In theevent that the handle 47 is released at a position where the lug 46 isaligned with the land, 45, the door will be free to move relative to thetrack only a short distance and, as soon as the lug 46 is aligned with aslot 44, the bias of the spring 39 will force the lug into the slotwhereby to latch the door in position. The lateral movement which occursupon closing the door 12 serves to disengage the latch mechanism 33 fromthe track 13. However, the bias of the spring 39 is restrained by theengagement of the upper surface of the arm 35a, 35b with the retainingplate 42 on the arms 50a, 50b.

It is believed apparent that with the device above described, the door12 is precluded from rolling movement relative to the railroad car. Fromcomputations that have been made, the force on a 1200-lb. door which issecured to a railroad car impacted by another car at humping speed is inthe order of 12,000 lbs. Obviously, a force of 12,000 lbs. is moreeasily absorbed than the force of 70,000 lbs. which was developed, asdescribed above, when the door was free rolling.

Further, the above-described derailment problem has been obviated withthe instant latching device. Inasmuch as the center of gravity of thedoor lies midway between the two roller hangers 26, 27 and the latch 33is in critical alignment with this point, any overturning couple presentis insufficient to raise the door from the track. Also, any upwardmovement of the door is prevented by the abutment of the upperv surfaceof the lug 46 with the track slot 44.

Other modes of accomplishing the results disclosed above will beapparent to those having ordinary skill in the art. Thus, a frictionmember might be used in lieu of the lug and slot arrangementillustrated. Also, the actuating handle might be made integral with thelug carrying memben These. two alternatives are purely illustrative andnot meant to be an exhaustive listing of the variations contemplated bythis invention.

For ease of description, the principles of the invention have been setforth in connection with but a single illustrated embodiment. It is notmy intention that the illustrated embodiment or the terminology employedin describing it be limitinginasmuch as variations in these may be madewithout departingfrom the spirit of the invention, but rather, it is mydesire to be restricted only by the scope of the appended claims.

I claim:

1. In combination,

a railroad car having a door opening,

a door adapted to close the opening in the car,

a track spaced from and secured to said car and mounting said door forlongitudinal movement therealong,

said track having a plurality of slots spaced along the longitudinallength thereof and facing said door with a portion of said trackcovering the slots on the side of the track opposite to the door,

latch means mounted on said door for movement toward and away from saidtrack,

said latch means having a portion adapted to enter the slots in saidtrack thereby to secure said door in a plurality of positions along thelength of said track and prevent movement of said door relative to saidcar.

2. In combination,

a door adapted to close an opening in a railroad car,

a track on the car,

means rollingly mounting said door on said track,

operating means on said door for displacing said door from the dooropening,

said track having a plurality of slots spaced along the longitudinallength thereof, with the slots facing said door,

latch means pivotally secured to said door,

said latch means having a portion adapted to enter the slots in saidtrack,

a handle separate from said latch means,

means pivotally mounting said handle on said door,

said handle including a portion thereon adapted to abut said latch meansin at least one position of said handle whereby said latch means may becaused to pivot on said door.

3. The combination of claim 2 wherein said latch means includes,

biasing means adapted to bias said portion of said latch means into theslots in said track when said portion is aligned with any of the slots.

4. In combination,

a door adapted to close an opening in a railroad car,

a track on the car,

means rollingly mounting said door on said track,

operating means on said door for displacing said door from the dooropening,

said track having a plurality of slots spaced along the longitudinallength thereof,

latch means pivotally secured to said door,

said latch means having a portion adapted to enter the slots in saidtrack thereby to secure said track in a plurality of positions along thelength of said track,

biasing means adapted to bias said portion of said track means intoengagement with the slots in said track, and

manually operable handle means on said door movable independently ofsaid latch means and being operable to disengage said portion of saidlatch means from said slots in said track against the bias of saidbiasing means,

5. In combination,

a door adapted to close an opening in a wall,

a track secured to the Wall and mounting said door for longitudinalsliding movement therealong,

said track having a plurality of slots spaced along the longitudinallength thereof,

latch means pivotally mounted on said door for swinging movement towardand away from said door,

said latch means having a portion adapted to enter the slots in saidtrack thereby to secure said door in a plurality of positions along thelength of said track,

said latch means comprising a lever pivotally mounted on the door,

said lever including a depending leg portion and bifurcated armportions,

said portion of said latch means comprising a lug on said leg portion,

biasing means normally biasing said lever to a position wherein said lugis in engagement with a slot in said track, and

a handle pivotally secured to the door, said handle having spaced apartarms adapted to engage said bifurcated arm portions of said lever andpivot said lever against the bias of said spring thereby to withdrawsaid lug from a slot in said track.

6. A latching mechanism adapted to restrain the movement of a slidingrailroad car door comprising,

a lever pivotally secured to the door,

said lever including a depending leg portion and bifurcated armportions,

a lug projecting from the lower end of said depending leg portion andadapted to enter slots spaced along the track mounting said door,

biasing means cooperating With said lever to bias said lug into one ofthe slots,

a handle secured to the door for pivotal movement,

said handle including spaced apart arms adapted to cooperate with thebifurcated arms on said lever whereby, upon pivoting of said handle inone direction, one of said spaced apart arms abuts one of saidbifurcated arms on said lever causing said lever to be pivoted againstthe bias of said spring and withdraw said lug from its associated slot.

References Cited by the Examiner UNITED STATES PATENTS 1,430,555 10/1922Jager 2022 1,468,053 9/ 1923 Townsend 2019 X 2,699,204 1/ 1955 Davis2052.8

FOREIGN PATENTS 598,200 5/1960 Canada. 702,564 1/1931 France.

HARRISON R. MOSELEY, Primary Examiner.

4. IN COMBINATION, A DOOR ADAPTED TO CLOSE AN OPENING IN A RAILROAD CAR,A TRACK ON THE CAR, MEANS ROLLINGLY MOUNTING SAID DOOR ON SIAD TRACK,OPERATING MEANS ON SAID DOOR FOR DISPLACING SAID DOOR FROM THE DOOROPENING, SAID TRACK HAVING A PLURALITY OF SLOTS SPACED ALONG THELONGITUDINAL LENGTH THEREOF, LATCH MEANS PIVOTALLY SECURED TO SAID DOOR,SAID LATCH MEANS HAVING A PORTION ADAPTED TO ENTER THE SLOTS IN SAIDTRACK THEREBY TO SECURE SAID TRACK IN A PLURALITY OF POSITIONS ALONG THELENGTH OF SAID TRACK, BIASING MEANS ADAPTED TO BIAS SAID PORTION OF SAIDTRACK MEANS INTO ENGAGEMENT WITH THE SLOTS IN SAID TRACK, AND MANUALLYOPERABLE HANDLE MEANS ON SAID DOOR MOVABLE INDEPENDENTLY OF SAID LATCHMEANS AND BEING OPERABLE TO DISENGAGE SAID PORTION OF SAID LATCH MEANSFROM SAID SLOTS IN SAID TRACK AGAINST THE BIAS OF SAID BIASING MEANS.